Expression Of P27, PCNA And TopoⅡα In Adrenal Cortical Neoplasm And Their Relationships To The Biological Behavior

Objective To study the expression of P27, proliferating cell nuclear antigen (PCNA) and DNA topoisomeraseⅡalpha (TopoⅡα) in adrenal cortical neoplasm and the relationship between their expression and the biological behavior of adrenal cortical neoplasm.Methods 55 samples of adrenal cortical neoplasm were obtained at operations performed at Tongji Hospital in 1994-2004, including 38 adrenal adenomas (including 12 aldosterone-producting adenomas, 13 glucocorticoid-producting adenomas and 13 unfunctional cortical adenomas ) and 17 adrenal carcinomas (including 5 carcinomas with infiltration and metastasis, 5 high differentiated carcinomas, 12 carcinomas with hormone- excreting function). 10 samples of normal adrenal cortex from Tongji Hospital Institute of Organs-transplantation were selected as contrast. The tissue specimens were dissected, and visible medullary parts were carefully separated. Tissues were fixed in buffered 10% formalin fixation fluid and routinely processed for light microscopic study. Sections of 5-μm were cut from paraffin-embedded blocks, deparaffinized in xylene, and rehydrated in a series of graded alcohols. The sections were stained by S-P immunohistochemical method according to the manufacturer's instructions and stained with hematoxylin-eosin. The positive expression of PCNA,TopoⅡαand P27 was observed and examined under the light microscope. All related data were collected depending on study design and SPSS (vision 12.0) statistical package was used to analysis.Results①T he expression of P27 in adrenal carcinoma was apparently weaker than in normal adrenal cortex and adenoma (p<0.05), whereas the expression of PCNA and TopoⅡαin carcinoma were apparently stronger than in normal adrenal cortex and adenoma (p<0.01).②There was no significant difference among the above markers between the normal adrenal cortex and adenoma (P>0.05).③There was no significant difference to the expression of the three markers in the three adenomas subgroups (P>0.05). The expression of the three markers has no apparent correlation with how much the hormone was excreted by the adenomas.④The expression of PCNA was positive correlated with that of TopoⅡα(r=0.78,P<0.01), PCNA was negative correlated with P27(r=-0.48,P<0.01),and TopoⅡαwas negative correlated with P27(r=-0.36,P<0.01).⑤The expression of P27 in carcinomas with metastasis were significantly lower than those without metastasis (P>0.05). There was no significant difference among the three markers between the high differentiated carcinomas and the low differentiated (P>0.05). And there was no significant difference between the functional carcinomas and the nonfunctional carcinomas (P>0.05).Conclusions The decreased expression of P27 and increased expression of PCNA and TopoⅡαmay be applicable to deciding the degree of malignancy of adrenal cortical neoplasm. To examine these three markers will be helpful to predicting the biological behavior of adrenal neoplasm.